System and method for forming porous bone filling material

Abstract

A method for treating a vertebral bone comprises providing a gaseous substance and providing a flowable and settable bone filling material. The method further comprises introducing the gaseous substance into the bone filling material to form a porous bone augmentation material and inserting a material delivery device into the vertebral bone. The method further comprises injecting the porous bone augmentation material from the material delivery device and into the vertebral bone.

What is claimed is: 
     
       1. A bone augmentation system comprising:
 a first vessel at least partially filled with a gaseous substance; 
 a second vessel at least partially filled with a flowable and settable bone filling material; 
 a mixing vessel in fluid communication with both the first and second vessels to receive the gaseous substance and the flowable and settable bone filling material, the mixing vessel including a mixing mechanism for mixing the gaseous substance and the bone filling material to form a bone augmentation material, the mixing mechanism comprising a plurality of projections extending from an inner surface of the mixing vessel configured to disperse the gaseous substance throughout the bone filling material; and 
 a dispensing instrument comprising a dispensing reservoir for receiving the bone augmentation material and comprising a cannulated member adapted to deliver the bone augmentation material into a body region adjacent cancellous bone. 
 
     
     
       2. The bone augmentation system of  claim 1  further comprising:
 a control mechanism disposed between the first vessel and the mixing vessel. 
 
     
     
       3. The bone augmentation system of  claim 2  wherein the control mechanism comprises a valve adapted to regulate the flow of the gaseous substance. 
     
     
       4. The bone augmentation system of  claim 1  wherein the mixing mechanism comprises a gas diffuser. 
     
     
       5. The bone augmentation system of  claim 1  wherein the mixing mechanism comprises an agitator. 
     
     
       6. The bone augmentation system of  claim 1  wherein the second vessel comprises a material reservoir and a plunger member movable through the material reservoir to push at least a portion of the flowable and settable bone filling material from the material reservoir. 
     
     
       7. The bone augmentation system of  claim 1  wherein the first vessel is a pressurized cartridge of carbon dioxide. 
     
     
       8. The bone augmentation system of  claim 1  wherein the first vessel comprises a material reservoir and a plunger member movable through the material reservoir to push at least a portion of the gaseous substance from the material reservoir. 
     
     
       9. The bone augmentation system of  claim 1  wherein the bone augmentation material comprises pores and 90% of the pores are in the range of 10 to 1000 microns. 
     
     
       10. The bone augmentation system of  claim 1  wherein the mixing vessel comprises an elongate inner surface and the plurality of projections are spaced apart along at least a partial length of the elongate inner surface. 
     
     
       11. The bone augmentation system of  claim 1  wherein the gaseous substance is air or carbon dioxide. 
     
     
       12. The bone augmentation system of  claim 1  wherein the flowable and settable bone filling material comprises polymethylmethacrylate, calcium phosphate, calcium sulfate, hydroxyapatite, or a combination thereof. 
     
     
       13. The bone augmentation system of  claim 1  wherein the bone augmentation material has a lower modulus of elasticity than the bone filling material when hardened.